He has a point - as such.
Wesley fails to acknowledge that it is Agrippa talking to a chained Paul who made the quote - which is more accurately render - 'Are you so quickly persuading me to become a Christian?'
It is not clear what Agrippa actually means by his question. Is he thinking of becoming a Christian? Hardly. Is he having something of a joke with Paul's beliefs? Perhaps. Or is Agrippa secularizing Christianity? Probably.
What Wesley is alluding to is the age old question - if I am genuinely motivated by virtue, will I gain access to God's Kingdom?
The question raises the whole issue of 'works' based salvation on which much has been said. In other words, reading Paul further, is it good enough just to 'perform' a bit role of a Christian? The unanimous voice from the world is a resounding - Yes. Wesley, the evangelist, answers with a resounding, No. Which raises a whole range of questions which Wesley subsequently attempts to address.
Wesley's main thrust is that if it is good enough for Christ to have died so 'we might live' then it is perhaps beholden to us to do something more than adopt a 'bit' role as a Christian.
But my question is - can we ever do anything other than to 'pretend', to the very best of our ability, to be a Christian?